Combination sheath and catheter for cardiovascular use

ABSTRACT

A vascular interventional device may be introduced over a guidewire into a vessel of the cardiovascular system of a patient. This device includes a hollow, flexible tube having a proximal end and a distal end that is adapted to selectively engage a target vessel of the cardiovascular system of the patient. This tube also includes a lumen that is continuous from the proximal to the distal end, and has an end hole in the distal end that is in fluid communication with the lumen. A plurality of side holes are provided near the distal end of the tube, each of which is in continuous fluid communication with the lumen. The device also includes a hollow vessel dilator that is adapted for insertion into and through the tube and over the guidewire. The dilator has an inside diameter that is slightly larger than the guidewire and an outside diameter that is slightly smaller than the diameter of the lumen of the tube. The distal end of the dilator is adapted to accommodate vascular entry over the guidewire, and the dilator is adapted to dilate the vessel to accept the tube. The device also includes a hub at the proximal end of the tube. The hub includes an end port through which a second interventional device having an outside diameter smaller than the diameter of the lumen may be introduced into the lumen of the tube. The hub also includes a side port through which a fluid agent may be injected for delivery through the lumen and out the end hole and side holes of the tube. A sealing mechanism is also provided in the hub to prevent air from entering the tube and blood and other fluids from leaking out of the tube through the hub. A pair of vascular interventional devices, at least one of which is constructed according to the invention, may be utilized to treat or study a cardiovascular condition, or to measure the blood pressure across a vascular segment.

FIELD OF THE INVENTION

This invention relates generally to a vascular interventional devicethat may be introduced over a guidewire into a vessel of thecardiovascular system of a patient. More particularly, the inventionrelates to such a device that functions both as a vascular entry sheathand as a diagnostic or therapeutic catheter. Such a device is capable ofdelivering both diagnostic and/or therapeutic agents, as well as otherinterventional devices, to a specific target portion of thecardiovascular system of a patient.

EXPLANATION OF TECHNICAL TERMS

As used herein, a vascular interventional device or interventionaldevice is any device that may be passed through a portion of thecardiovascular system of a patient for diagnostic or therapeuticpurposes, including diagnostic and therapeutic catheters. The term alsoincludes components of such devices and other instruments that may beused to facilitate the passage of such devices within the cardiovascularsystem, such as guidewires, dilators and sheaths.

As used herein, a patient may be a human or another mammal.

As used herein, vessels of the cardiovascular system of a patient orblood vessels include arteries and veins and branches thereof ortherefrom, and other tubes, chambers and ducts that carry blood.

As used herein, a vessel of entry is a vessel that is entered fromoutside the body of the patient.

As used herein, a target vessel or branch of a vessel is a portion ofthe cardiovascular system of a patient that is targeted for diagnosis ortherapy, or that provides a pathway to such portion from a vessel ofentry. A target vessel may also be a vessel of entry.

As used herein, a vascular segment is a portion of a vessel.

As used herein, a vascular interventional device or a component thereofmay be adapted to selectively engage a target vessel or branch of avessel. Such a device or component may be shaped, formed or manipulatedso that when it is advanced to a location adjacent to the target vesselor branch, further advancement will cause the distal end of the deviceto enter the target vessel or branch.

As used herein, a guidewire is a device that may be used in positioningand moving a diagnostic or therapeutic vascular interventional device.

As used herein, a sheath is a tube that may be used to facilitate thepassage of a vascular interventional device within the cardiovascularsystem of a patient.

As used herein, a dilator is a vascular interventional device or acomponent thereof that may be used to dilate a portion of one or morevessels of the cardiovascular system so as to facilitate entry orpassage of another vascular interventional device or component thereof.

As used herein, a catheter is a vascular interventional device that maybe used for diagnostic or therapeutic purposes.

As used herein, a fluid agent is a drug or other fluid that may beinjected into a portion of the cardiovascular system for therapeutic ordiagnostic purposes.

As used herein, a fluid agent is delivered to a target portion of thecardiovascular system of a patient at a clinically effective rate or aneffective rate when said agent is delivered at a flow rate that issuitable for the effective use of the fluid agent and at a velocity thatis unlikely to cause injury or damage to the target portion of thecardiovascular system.

As used herein, a contrast agent, medium or fluid is a radiopaque fluidagent that may be used to provide a contrast in density with tissue,structures or another object for x-ray or other radiologicalexamination.

As used herein, the French scale is a measurement system that may beused to indicate the diameter of a vascular interventional device or acomponent thereof. Each unit on the scale is equal to 1/π , millimeters.

BACKGROUND AND DESCRIPTION OF THE PRIOR ART

In conventional practice, access to a vessel of the cardiovascularsystem of a patient may be obtained using a vascular entry sheath.Generally, a needle is used to puncture a blood vessel of entry (such asan artery), and a guidewire is passed through the needle to a desiredlocation in the vessel. The needle is withdrawn and the guidewire ismaintained in position in the vessel. Then a short sheath is advancedinto the vessel over the guidewire to facilitate introduction of adiagnostic or therapeutic catheter. A catheter is advanced through thesheath, and the guidewire may then be removed. Once the distal end ofthe catheter is advanced to the target vessel, diagnostic or therapeuticprocedures may be carried out. Depending on the type of catheteremployed, fluid agents may be injected through the catheter fordiagnostic or therapeutic purposes. However, if it is necessary ordesirable to inject an x-ray contrast agent into a target vessel, alarge caliber catheter must be advanced through the sheath to the targetvessel, so as to provide for sufficiently high flow rates to displaceblood with contrast agent. In most cases, the sheath itself may notserve as the conduit for delivery of contrast agent because conventionalsheaths are usually quite short and are not adapted to selectivelyengage a vessel of the cardiovascular system. Furthermore, conventionalsheaths have only a single end hole, and fluid injected therethrough involumes sufficient for a contrast agent would likely flow from the endhole at such a velocity that tissue damage might occur. Consequently, aconventional sheath is used only to provide access to the vessel ofentry, and a catheter is advanced through the sheath to reach a targetvessel. If it is desired to deliver a fluid agent such as contrast fluidto a segment of the target vessel, it is generally necessary to employ adiagnostic catheter. If it is desired, after imaging of the target area,to employ another therapeutic or diagnostic device, the diagnosticcatheter must first be removed, so that a second interventional devicemay be advanced to the target area.

Various catheters for distribution of fluid agents (sometimes referredto as infusion catheters) are known. For example, U.S. Pat. No.5,021,044 of Sharkawy describes a vascular catheter having an innerlumen for receiving a guidewire and at least one concentrically disposedouter lumen for delivery of a fluid agent. The outer lumen is providedwith a number of flow passageways to maintain a desired flow pattern tothe target site, typically of about 0.1-1.5 cm³/hour. U.S. Pat. No.5,599,324 of McAlister et al. and U.S. Pat. No. 5,709,874 of Hanson etal. describe similar multi-lumen catheters. U.S. Pat. No. 5,380,307 ofChee et al. and U.S. Pat. No. 5,425,723 of Wang describe perfusioncatheters that are designed to deliver a fluid agent through side holesuniformly along a perfusion portion of the catheter. These devicesoperate to deliver fluid to a target point within a vessel at low flowrates that are useful for introduction of pharmacological agents such asthrombolytic drugs, but are wholly insufficient for proper introductionof a contrast agent. Furthermore, these devices do not accommodate orfacilitate the introduction of a second interventional device into thecardiovascular system of a patient.

U.S. Pat. No. 5,569,197 of Helmus et al. describes a hollow infusionguidewire over which a catheter may be introduced into a vessel.Preferably, the Helmus guidewire has an outer diameter that iscomparable to that of a standard coronary guidewire, typically about0.014 inch. It also has a plurality of openings or perforations in thesidewall near its distal end for dispersal of a drug therethrough.However, since it is sized to function as a guidewire too, it may onlybe used to disperse fluid at the target location at a very low rate,thereby limiting its use to the delivery of drugs only.

Many of the known infusion guidewires include complicated multi-lumenalstructures and valve arrangements that are difficult and expensive tomanufacture. Furthermore, these devices generally operate to deliverfluid agents to a target site at low flow rates that are whollyinsufficient for use in delivering contrast media. Other devices thatmay be employed to deliver contrast media at an appropriate rate permitflow at a velocity that is likely to cause tissue damage. Thus, forexample, U.S. Pat. No. 5,180,364 of Ginsburg describes a self-perfusingguiding catheter that is adapted for delivery of contrast media througha central lumen. The catheter includes a number of holes or slits thatare provided with one-way valves so as to selectively permit fluidcommunication between the central lumen and the exterior of the device.When contrast media is injected through the central lumen, the valvesclose so that all of the contrast fluid is delivered out the end of thedevice. When no fluid is injected, the valves open to prevent the devicefrom blocking blood flow within the vessel by permitting perfusing bloodto flow into and through the catheter. After imaging of the target areais obtained, as by radiographic examination of the contrast media, asecond catheter may be introduced through the central lumen and advancedto the target area. However, when the Ginsburg device is used to delivera significant volume of contrast fluid in order to displace bloodvolume, the velocity of delivery of contrast fluid out the end hole maybe so great that tissue damage may occur.

It would be desirable therefore if a vascular interventional device weredeveloped that would be relatively simple and inexpensive tomanufacture. It would also be desirable if such a device were developedthat could be used to deliver fluid such as contrast media to a targetarea at a rate sufficient to displace blood so that a radiologicexamination of the target area could provide useful information, but ata velocity that would minimize tissue damage. In addition, it would bedesirable if such a device were developed that could be used to deliverfluid at an effective rate while a second interventional device wasbeing used to diagnose or treat a condition.

OBJECTS AND ADVANTAGES OF THE INVENTION

Accordingly, it is an object of the invention claimed herein to providea vascular interventional device that may be manufactured relativelyeasily and inexpensively. It is also an object of the invention toprovide such a device which may be used to deliver a fluid agent to atarget vessel or vessel segment at a clinically effective rate. Anotherobject of the invention is to provide such a device that may also beused to deliver a second interventional device to a target vessel orvessel segment, which device may be used for therapeutic or diagnosticpurposes while the fluid agent is being delivered at a clinicallyeffective rate. It is yet another object of the invention to providesuch a device that is adapted to selectively engage a target vessel ofthe cardiovascular system of a patient. It is still another object ofthe invention to provide a method for treating or studying acardiovascular condition of a patient. It is yet another object of theinvention to provide a method to measure the difference in bloodpressure (if any) across a vascular segment of the cardiovascular systemof a patient.

Additional objects and advantages of this invention will become apparentfrom an examination of the drawings and the ensuing description.

SUMMARY OF THE INVENTION

A vascular interventional device is provided that may be introduced overa guidewire into a vessel of the cardiovascular system of a patient.This device includes a hollow, flexible tube having a proximal end and adistal end, and a lumen that is continuous from the proximal to thedistal end. An end hole in the distal end is in fluid communication withthe lumen, and a plurality of side holes are provided near the distalend of the tube, each of which is in continuous fluid communication withthe lumen. The distal end of the tube is adapted to selectively engage atarget vessel of the cardiovascular system of the patient. The devicealso includes a hollow vessel dilator that is adapted for insertion intoand through the tube and over the guidewire. The dilator has an insidediameter that is slightly larger than the guidewire, and an outsidediameter that is slightly smaller than the diameter of the lumen of thetube. The distal end of the dilator is tapered to accommodate vascularentry over the guidewire. The dilator is adapted to dilate the vessel toaccept the tube. The device also includes a hub at the proximal end ofthe tube. The hub includes an end port through which a secondinterventional device having an outside diameter smaller than thediameter of the lumen (including a second interventional device having apressure transducer connected thereto) may be introduced into andthrough the lumen of the tube. The hub also includes a side port throughwhich a fluid agent may be injected for delivery through the lumen andout the end hole and side holes of the tube, or through which pressurescan be measured, using a pressure transducer that may be connectedthereto. A sealing mechanism is also provided in the hub to prevent airfrom entering the tube and blood and other fluids from leaking out ofthe tube through the hub.

The invention also includes a method for treating or studying acardiovascular condition of a patient, using two vascular interventionaldevices, at least one of which (a first vascular interventional device)includes a hollow, flexible tube, a hub and a dilator, as describedabove. According to this method, a guidewire is inserted into a vesselof the cardiovascular system of a patient in the conventional manner.The dilator of the first device is then inserted into the tube with itsdistal end protruding from the distal end of the tube. The dilator andtube are then inserted into the vessel over the guidewire and positionedin the target area. The dilator is then withdrawn through the tube fromthe cardiovascular system of the patient. A second interventional deviceis selected to treat or study the cardiovascular condition, and thesecond device is introduced through the end port of the hub of the firstdevice. The second interventional device is advanced over the guidewireto the distal end of the tube of the first device, and the guidewire isthen removed. A fluid agent is then injected through the side port fordelivery through the lumen around the second vascular interventionaldevice, and out the end hole and side holes of the tube. The secondinterventional device is employed to treat or study the cardiovascularcondition.

The invention also includes a method for using a pair of vascularinterventional devices to measure the difference in blood pressuresacross a vascular segment of the cardiovascular system of a patient. Themethod includes providing a first vascular interventional device thatincludes a hollow, flexible tube, a hub and a dilator, as describedabove. A guidewire is inserted into a vessel of the cardiovascularsystem of a patient in the conventional manner. The dilator of the firstdevice is then inserted into the tube with its distal end protrudingfrom the distal end of the tube. The dilator and tube are then insertedinto the vessel over the guidewire and the distal end of the tube ispositioned at a first location in the target area. The dilator is thenwithdrawn from the cardiovascular system of the patient and is removedfrom the tube. A first pressure transducer is attached to the side portof the first device. A second interventional device, which is suitablefor use in measuring the blood pressure at a point in the cardiovascularsystem, is selected and introduced through the end port of the hub ofthe first device. The second interventional device is advanced over theguidewire so that its distal end is located at a second location beyondthe first location (beyond the distal end of the tube of the firstdevice). The guidewire is then removed, and a second pressure transduceris attached to the proximal end of the second interventional device. Theblood pressure is then measured simultaneously at the distal end of thetube of the first interventional device (the first location) and at thedistal end of the second interventional device (the second location).The difference in blood pressure, if any, between the first and secondlocations is then calculated.

In order to facilitate an understanding of the invention, the preferredembodiments of the invention are illustrated in the drawings, and adetailed description thereof follows. It is not intended, however, thatthe invention be limited to the particular embodiments described or touse in connection with the apparatus illustrated herein. Variousmodifications and alternative embodiments such as would ordinarily occurto one skilled in the art to which the invention relates are alsocontemplated and included within the scope of the invention describedand claimed herein.

BRIEF DESCRIPTION OF THE DRAWINGS

The presently preferred embodiments of the invention are illustrated inthe accompanying drawings, in which like reference numerals representlike parts throughout, and in which:

FIG. 1 is a plan view of a preferred embodiment of the invention.

FIG. 2 is a plan view of a second embodiment of a portion of theinvention.

FIG. 3 is a plan view of a third embodiment of a portion of theinvention.

FIG. 4 is a plan view of a fourth embodiment of a portion of theinvention.

FIG. 5 is a plan view of a fifth embodiment of a portion of theinvention.

FIG. 6 is an enlarged sectional view of a portion of the device of FIG.1, taken along the line 6—6 of FIG. 1.

FIG. 7 is an enlarged sectional view of a portion of the device of FIG.1, taken along the line 7—7 of FIG. 1.

FIG. 8 is an enlarged sectional view of a portion of the device of FIG.1, taken along the line 8—8 of FIG. 1.

FIG. 9 is an enlarged sectional view of an alternative embodiment of theportion of the device illustrated in FIG. 8.

FIG. 10 is an enlarged sectional view of an alternative embodiment ofthe portion of the device illustrated in FIGS. 8 and 9, which employs aTouhy-Borst type sealing mechanism, illustrating the sealing mechanismin an open configuration.

FIG. 11 is an enlarged sectional view of the portion of the deviceillustrated in FIG. 10, illustrating the sealing mechanism in an closedconfiguration.

DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION

Referring now to the drawings, FIG. 1 illustrates a preferred embodiment10 of a vascular interventional device that may be introduced over aguidewire (not shown) into a vessel of the cardiovascular system of apatient. Generally, a needle (not shown) is used to puncture a bloodvessel of entry (such as an artery), and a guidewire (also not shown) ispassed through the needle to a desired location in the vessel. Theneedle is withdrawn and the guidewire is maintained in position in thevessel. Then the vascular interventional device 10 may be introducedinto the vessel of entry over the guidewire, and guided or manipulatedto a target vessel.

Device 10 includes hollow, flexible tube 12 having proximal end 14 anddistal end 16. Tube 12 is provided in any convenient length anddiameter, depending on its intended use. The distal end of the tube isadapted to selectively engage a target vessel of the cardiovascularsystem of the patient. Such adaptation may be accomplished by providingthe tube with a preformed shape of any convenient length andconfiguration. The tube may be straight, or it may be provided withcurves of various radii, or with bends of varying angles, depending onthe application for which it is intended. Preferably, the distal end ofthe tube is preformed so as to select a desired path into or through avessel selected from the group consisting of common femoral arteries,profunda femoral arteries, superficial femoral arteries, common iliacarteries, internal iliac arteries, external iliac arteries, mesentericarteries, renal arteries, gastric arteries, hepatic arteries, splenicarteries, pulmonary arteries, subclavian arteries, common carotidarteries, internal carotid arteries, external carotid arteries,innominate arteries and coronary arteries. Thus, for example, tube 12 ofdevice 10 is provided with a preformed shape that is adapted to select atarget vessel such as an iliac artery on one side of the patient's body,for example, from a vessel of entry such as the corresponding iliacartery on the other side of the body. By contrast, tube 112 of device110, illustrated in FIG. 2, is provided with a preformed shape that isadapted to select a target vessel such as the superior mesenteric arteryor the renal artery, for example, from a vessel of entry such as thecommon femoral artery. Similarly, tube 212 of device 210, illustrated inFIG. 3, is provided with a preformed shape that is adapted to select atarget vessel such as the innominate artery or the carotid artery, forexample, from a vessel of entry such as the common femoral artery. Inaddition, tube 312 of device 310, illustrated in FIG. 4, is providedwith a preformed shape that is adapted to select a target vessel such asone of the renal arteries, for example, from a vessel of entry such asthe common femoral artery. Another example is illustrated in FIG. 5,wherein tube 412 of device 410 is provided with a multipurpose preformedshape that is adapted to select any of a variety of target vessels froma vessel of entry.

Referring again to FIG. 1, tube 12 includes a lumen that is continuousfrom proximal end 14 to distal end 16, and an end hole in the distal endthat is in fluid communication with the lumen. The tube is provided witha lumen having a diameter that is suitable for the intended use ofdevice 10. Preferably, the tube has a minimum lumen diameter of about 3on the French scale. Tube 12 also includes a plurality of side holes 18near the distal end thereof, each of which is in continuous fluidcommunication with the lumen. Preferably, the tube includes at least oneradiopaque marker at or near its distal end. Most preferably, two suchmarkers are provided, marker 20 that is located at the distal end andmarker 22 that is located adjacent to the side hole nearest the proximalend.

The device also includes a hollow vessel dilator that is adapted forinsertion into and through the tube and over the guidewire. The dilatorhas an inside diameter that is slightly larger than the guidewire, andan outside diameter that is slightly smaller than the diameter of thelumen of the tube. By virtue of its size and shape, especially of distaltip 24 (illustrated in FIG. 1), the dilator is adapted to accommodatevascular entry over the guidewire, so that it may dilate the vessel ofentry to accept the tube. Preferably, the distal tip of the dilator ispreformed so as to select a desired path into or through a vessel of thecardiovascular system of the patient. It is also preferred that thedilator is adapted to be removable from the vessel through the tubeafter the tube has been inserted into the vessel.

Hub 26 is located at the proximal end of tube 12, and is attachedthereto by force-fit, welding or other means known to those havingordinary skill in the art to which the invention relates. Hub 26 may beformed of polyethylene or other suitable material, and it may also beprovided in several components, including attachment member 28A andsecondary hub portion 29A (see FIG. 8), attachment member 28B andsecondary hub portion 29B (see FIG. 9), or attachment member 28B andsecondary hub portion 29C (see FIGS. 10 and 11). Preferably, tube 12 hasa flared portion 30 at its proximal end and an annular shoulder 32adjacent thereto that is adapted to provide a hub seat therebetween.Attachment member 28A or 28B of the hub is adapted to seat betweenflared proximal end 30 and shoulder 32 of the tube. In the embodiment ofthe hub illustrated in FIG. 8, a gasket, such as O-ring 34, may also beprovided to seal the attachment member of the hub to the proximal end ofthe tube against leakage of blood or other fluid. In this embodiment,attachment member 28A is fixed to secondary hub portion 29A, and isadapted to rotate around the O-ring about axis 35 of tube 12 forpurposes that will be subsequently explained. Other mechanisms forsealing against leakage of blood or other fluid between the attachmentmember of the hub and the proximal end of the tube, and for permittingrotation of at least a portion of the hub about axis 35 may also beprovided. Two other alternative embodiments of the hub, illustrated inFIGS. 9 and 10-11, will also be described and explained.

Hub 26 includes end port 36 (see FIG. 1) through which a secondinterventional device (not shown) having an outside diameter smallerthan the diameter of the lumen of tube 12 may be introduced through theend hole and into the lumen of the tube. Preferably, the hub is adaptedto accommodate a second interventional device selected from the groupconsisting of guidewires, infusion guidewires, balloon angioplastycatheters, laser angioplasty catheters, rotational ablation catheters,atherectomy catheters, infusion catheters and diagnostic catheters.

Hub 26 also includes side port 38 (see FIG. 1), comprised of tube mount40, side tube 42 and valve body 44, through which a fluid agent may beinjected for delivery through the lumen and out the end hole and sideholes of the tube. Valve body 44 includes a pair of entry ports 46 and48 through which a fluid agent may be injected, and a valve 50 which maybe operated to selectively open and close the entry ports.

Preferably, the dilator has a terminus 52 at its proximal end, which ismounted on the dilator so as to rotate thereabout. The terminus may beexternally threaded through a portion thereof so as to be attached tomating internally threaded portion 54 (see FIGS. 8-11) within end port36. In the alternative, the terminus may attach to the end port by snapfit or by other attachment means known to those having ordinary skill inthe art to which the invention relates. When it is desired to remove thedilator from the cardiovascular system of a patient, the terminus isunthreaded from end port 36 so that the dilator may be removed throughthe tube.

Hub 26 also includes a sealing mechanism that prevents air from enteringthe tube and blood and other fluids from leaking out of the tube throughthe hub. The sealing mechanism may be used to seal the hub around asecond interventional device that is in place in the hub, or it may sealthe hub in the absence of such a device. In the embodiment of FIGS. 7-9,the sealing mechanism is provided in the form of diaphragm 56.Preferably, the diaphragm is provided in the form of a thin, flexiblemembrane of latex, silicone or other suitable material, with at leastone and most preferably a series of slits 58 to permit the dilator or asecond interventional device to be introduced therethrough. Preferably,the diaphragm prevents air from entering the tube and blood and otherfluids from leaking out of the tube through the hub when the dilator isin place in the tube or when a second interventional device isintroduced and advanced through the end port of the hub. The diaphragmwill also preferably prevent air from entering the tube and blood andother fluids from leaking out of the tube through the hub when nodilator or second interventional device is in place in the tube. Anothertype of sealing mechanism, in the nature of a Touhy-Borst device, mayalso be used, as illustrated in FIGS. 10 and 11, which will be describedin more detail hereinafter.

Preferably, side port 38 of hub 26 is adapted to rotate about the longaxis of tube 12. This may be accomplished in several ways, three ofwhich are illustrated in FIGS. 8, 9 and 10-11. As shown in FIG. 8,attachment member 28A and secondary hub portion 29A may be fixedtogether, and attachment member 28A may be adapted for rotation abouttube 12 between flared portion 30 and shoulder 32. FIG. 9 illustrates asecond embodiment of the hub, in which attachment member 28B is providedwith an annular lip 60 at its lower end (as shown in FIG. 9), andretaining ring 61. Secondary hub portion 29B is also provided with anannular lip 62 at its upper end (as shown in FIG. 9) that may beretained within attachment member 28B and between its lip 60 and itsretaining ring 61 so that side port 38 of the hub may rotate about axis35 that extends generally along the length of the tube. Gasket 64 may beinterposed between lip 60 of attachment member 28B and lip 62 ofsecondary hub portion 29B in order to seal the hub assembly againstleakage of blood or other fluids.

FIGS. 10 and 11 illustrate a third embodiment of the hub which employs aTouhy-Borst type sealing mechanism. In this embodiment, secondary hubportion 29C is connected to attachment member 28B in the same manner asin the embodiment of FIG. 9 so that side port 38 of the hub may rotateabout axis 35. Secondary hub portion 29C includes inner component 66 andouter component 68. Inner component 66 is externally threaded withthreads 70. Outer component 68 is internally threaded with threads 72,which are adapted to mate with threads 70. Outer component 68 alsoincludes inner cylinder 74, which is hollow and opens at its outer endinto end port 36. Inner cylinder 74 is also internally threaded withthreads 54 that are adapted to mate with terminus 52 of the dilator. Atthe inner end of cylinder 74 is washer 76, a generally rigid, circularwasher having a central hole therethrough. Cylinder 74 of outercomponent 68 is adapted to move axially, as the outer component isthreaded onto the inner component, into receiving cylinder 78 of theinner portion. Located within the receiving cylinder is a compressiblegasket 80 which is provided with a central hole therethrough. Gasket 80is retained within the receiving cylinder by end wall 82, which also hasa central hole therethrough. When the hub of this embodiment is in theopen configuration illustrated in FIG. 10, there is an open passagewayfrom end port 36 through inner cylinder 74, washer 76, gasket 80, endwall 82 and the remainder of secondary hub portion 29C, attachmentmember 28B and into tube 12. A second interventional device may bepassed through this passageway into the cardiovascular system of apatient. When outer component 68 is advanced by threading it furtheronto inner component 66, washer 76 atop cylinder 74 compresses gasket 80against end wall 82 of receiving cylinder 78 so as to close its centralhole to seal the hub to prevent air from entering the tube and blood andother fluids from leaking out of the tube through the hub. The sealingmechanism may be used to seal the hub around a second interventionaldevice that is in place or in the absence of such a device.

Tube 12 and side tube 42 of device 10 may be formed from any suitablematerial known to those having ordinary skill in the art to which theinvention relates, and the dilator may be formed from similar material.Preferably, these components are made primarily of a synthetic material,although they may include a reinforcing mesh of metal, glass fibers orthe like, imbedded within the material of the tube. Good results may beexpected when the tube is made primarily of a material selected from thegroup consisting of polytetrafluorethylene, polyolefin, polyester,polyethylene and conjugates of such materials. Preferably, at least aportion of the outside of the tube is coated with lubricious material,such as silicone, so as to facilitate entry and passage of the tube intoand through the cardiovascular system of a patient.

The diameter of the lumen of the tube, and the number, shape and size ofeach of the side holes are such that a fluid agent may be delivered outthe end hole and side holes of the tube at a rate and velocitysufficient to displace blood from the portion of the vessel in which thedistal end of the tube resides without damaging such portion of thevessel. Preferably, the rate of flow out the end bole and side holes ofthe tube is at least about one cubic centimeter per second while asecond interventional device is in place in the distal end of the tube.Preferred results may be obtained when six circular side holes, eachhaving a diameter of about one millimeter, are provided in a spiralpattern around the periphery of tube at the distal end, and wherein theend hole of the tube has a diameter of at least about 3 on the Frenchscale.

The invention can be used to perform any of several diagnostic andtherapeutic procedures. For example, it can be employed in a method fortreating or studying a cardiovascular condition of a patient. Accordingto this method, a first vascular interventional device similar to device10 is provided. A guidewire (not shown) is inserted into a vessel of thecardiovascular system of a patient in the conventional manner. Thedilator of the first vascular interventional device is inserted into thetube of the first device so that its distal end protrudes from thedistal end of the tube. The dilator and tube are then introduced overthe guidewire into the vessel, and the distal end of the tube isadvanced to a location of interest, such as the location of a blockageor partial blockage in the vessel. The dilator of the first device maythen be withdrawn through the tube from the cardiovascular system of thepatient, and a second interventional device (not shown), which may beused to treat or study the cardiovascular condition, may then beselected. This device may be a guidewire or another device such as aballoon angioplasty catheter, a laser angioplasty catheter, a rotationalablation catheter or an atherectomy catheter. If the second device is aguidewire, the first guidewire is removed from the cardiovascular systemof the patient and the second introduced through the tube of the firstdevice. Otherwise, the second interventional device may be introducedthrough the end port of the first device, and advanced over theguidewire until its distal end reaches a point in the target vesselbeyond the distal end of the tube of the first vascular interventionaldevice. A fluid agent, such as X-ray contrast agents, thrombolyticagents, anticoagulants and platelet aggregation inhibitors, may then beinjected through the side port of the first device for delivery throughthe lumen around the second vascular interventional device, and out theend hole and side holes of the tube. It may be desired that the fluidagent, especially if it is an X-ray contrast agent, be delivered at arate and velocity sufficient to displace blood from the portion of thevessel in which the distal end of the tube resides without damaging suchportion of the vessel. Preferably, the rate of flow of an X-ray contrastagent out the end hole and side holes is at least about one cubiccentimeter per second. If the fluid agent employed is an X-ray contrastagent, a radiographic imaging device may be employed to examine thetarget location in the vessel while the second interventional device isin place within the vessel. The second device may then be employed totreat or study the cardiovascular condition.

The invention can also be used in a method for measuring the differencein blood pressures across a vascular segment of the cardiovascularsystem of a patient. According to such method, a first vascularinterventional device similar to device 10 is provided. The diameter ofthe lumen of the tube of this device, the number of side holes and theshape and size of each of the side holes are such that fluidcommunication may be maintained throughout the length of the tube whilea second interventional device is in place in the distal end of thetube. According to this method, a guidewire is inserted into a vessel ofthe cardiovascular system of a patient in the conventional manner. Thedilator of the first vascular interventional device is then insertedinto the tube so that its distal end protrudes from the distal end ofthe tube. The dilator and tube are then introduced over the guidewireinto the vessel, and the distal end of the tube is advanced to a firstlocation of interest (such as a location adjacent to a partial blockage,aneurysm or other vessel anomaly). The dilator of the first device isthen withdrawn from the cardiovascular system of the patient through andout of the tube of the first device, and a first conventional pressuretransducer is attached to the side port of the first device. A secondinterventional device which is adapted to measure the blood pressure ata point in the cardiovascular system is selected and introduced throughthe end port of the hub of the first device. The distal end of thesecond interventional device is advanced over the guidewire to a secondlocation that is beyond the first location (such as a location beyond apartial blockage, aneurysm or other vessel anomaly). The guidewire isremoved from the cardiovascular system of the patient, and a secondpressure transducer is attached to the proximal end of the seconddevice. The blood pressure may then be measured simultaneously at thedistal end of the tube of the first interventional device (the firstlocation) and at the distal end of the second interventional device (thesecond location). The difference in blood pressure between the first andthe second locations may also be calculated. Because the diameter of thelumen of the tube of the first interventional device, the number of sideholes, and the shape and size of each of the side holes are such thatfluid communication may be maintained throughout the length of the tubewhile a second interventional device is in place in the distal end ofthe tube, the pressure measurement taken at the first location mayaccurately represent the actual pressure at such location.

Although this description contains many specifics, these should not beconstrued as limiting the scope of the invention but as merely providingillustrations of some of the presently preferred embodiments thereof, aswell as the best mode contemplated by the inventor of carrying out theinvention. The invention, as described herein, is susceptible to variousmodifications and adaptations, and the same are intended to becomprehended within the meaning and range of equivalents of the appendedclaims.

What is claimed is:
 1. A vascular interventional device that may beintroduced over a guidewire into a vessel of the cardiovascular systemof a patient, said device comprising: (a) a hollow, flexible tubehaving: (i) a proximal end; (ii) a distal end that is adapted toselectively engage a target vessel of the cardiovascular system of thepatient; (iii) a lumen that is continuous from the proximal to thedistal end; (iv) an end hole in the distal end thereof that is in fluidcommunication with the lumen; and (v) a plurality of side holes near thedistal end thereof, each of which is in continuous fluid communicationwith the lumen; (b) a hub at the proximal end of the tube, said hubincluding: (i) an end port through which a second interventional devicehaving an outside diameter smaller than the diameter of the lumen may beintroduced into the lumen of the tube; and (ii) a side port throughwhich a fluid agent may be injected for delivery through the lumen andout the end hole and side holes of the tube; (iii) a sealing mechanismthat prevents air from entering the tube and blood and other fluids fromleaking out of the tube through the hub; (c) a flexible, hollow vesseldilator that is adapted for insertion into and through the tube and overthe guidewire, said dilator: (i) having a proximal end and a distal end,said distal end being adapted to accommodate vascular entry over theguidewire; (ii) having an inside diameter that is slightly larger thanthe guidewire; (iii) having an outside diameter that is slightly smallerthan the diameter of the lumen of the tube; (iv) being adapted to dilatethe vessel to accept the tube; and (v) being adapted for secure butremovable attachment to the hub at its proximal end.
 2. The device ofclaim 1 wherein the lumen diameter, the number of side holes and theshape and size of each of the side holes are selected so that a fluidagent may be delivered out the end hole and side holes of the tube at arate of at least about one cubic centimeter per second while a secondinterventional device is in place in the distal end of the tube.
 3. Thedevice of claim 1 wherein the tube has a minimum lumen diameter of about3 on the French scale.
 4. The device of claim 1 which is adapted toaccommodate a second interventional device selected from the groupconsisting of guidewires, infusion guidewires, balloon angioplastycatheters, laser angioplast catheters, rotational ablation catheters,atherectomy catheters, infusion catheters and diagnostic catheters. 5.The device of claim 1 wherein at least a portion of the outside of thetube is coated with lubricious material.
 6. The device of claim 1wherein the distal end of the tube is preformed so as to select adesired path into or through a vessel selected from the group consistingof common femoral arteries, profunda femoral arteries, superficialfemoral arteries, common iliac arteries, internal iliac arteries,external iliac arteries, mesenteric arteries, renal arteries, gastricarteries, hepatic arteries, splenic arteries, pulmonary arteries,subclavian arteries, common carotid arteries, internal carotid arteries,external carotid arteries, innominate arteries and coronary arteries. 7.The device of claim 1 wherein the dilator includes a tip at its distalend, which tip is preformed so as to select a desired path into orthrough a vessel of the cardiovascular system of the patient.
 8. Thedevice of claim 1 wherein the dilator includes a terminus at itsproximal end, which terminus is adapted to be attached to the hub. 9.The device of claim 1 wherein the tube has an axis along its length, andthe side port of the hub is adapted to rotate about the axis of thetube.
 10. The device of claim 9 wherein the hub includes an attachmentmember for attachment of the tube thereto, and a secondary hub portionto which the side port is attached, and wherein the attachment memberand the secondary hub portion are adapted to rotate with respect to eachother so that the side port may rotate about the axis of the tube. 11.The device of claim 1 wherein the tube includes at least one radiopaquemarker at or near its distal end.
 12. The device of claim 11 wherein thetube includes two radiopaque markers, one located at the distal end andthe other located adjacent to the side hole nearest the proximal end.13. The device of claim 1 wherein the tube is made primarily of asynthetic material.
 14. The device of claim 13 wherein the tube is madeprimarily of a material selected from the group consisting ofpolytetrafluorethylene, polyolefin, polyester, polyethylene andconjugates of such materials.
 15. The device of claim 13 wherein thetube includes a reinforcing mesh imbedded within the material of thetube.
 16. The device of claim 1 wherein the sealing mechanism preventsair from entering the tube and blood and other fluids from leaking outof the tube through the hub when a second interventional device isintroduced and advanced through the end port.
 17. The device of claim 16wherein the sealing mechanism is provided in the form of a diaphragmthat is comprised of a flexible membrane having at least one slit forintroduction of the second interventional device therethrough.
 18. Thedevice of claim 16 wherein the sealing mechanism includes a compressiblegasket having a central hole therethrough and a mechanism forcompressing said gasket so as to close its central hole.
 19. The deviceof claim 1 wherein the tube has a flared proximal end and an annularshoulder adjacent thereto with a hub seat therebetween, and wherein thehub is provided with a attachment member that is adapted to seat betweenthe flared proximal end and the shoulder of the tube.
 20. The device ofclaim 19 which includes a gasket that is adapted to seal the attachmentof the hub to the proximal end of the tube against leakage of blood orother fluids.
 21. The device of claim 20 wherein the attachment memberis adapted to rotate with respect to the gasket so that the side portmay rotate about the axis of the tube.